金佛山方竹经营对扁刺栲群落物种多样性和优势种种群结构的影响

为探讨金佛山方竹经营对扁刺栲群落物种多样性和优势种种群结构的影响,该研究以金佛山的扁刺栲自然群落和金佛山方竹经营群落为对象,分析了两类群落的物种组成特征、物种多样性及优势种种群结构。结果表明:(1)两种群落内共记录维管束植物84种,隶属于40科63属,以樟科、蔷薇科、壳斗科、山茶科物种为主; 扁刺栲为群落优势种,中华木荷和灰柯为次优势种,金佛山方竹为灌木层优势种,扁刺栲群落组成与亚热带其他地区的扁刺栲群落组成相似。(2)金佛山方竹经营群落的灌木层物种丰富度显著低于自然群落,草本层Shannon-Wiener指数和Pielou指数均显著低于自然群落。(3)扁刺栲和灰柯在自然群落中为稳定型种群,而在金佛山方竹经营群落中为衰退型种群,中华木荷在两类群落中均为衰退型种群。(4)自然群落中扁刺栲、中华木荷、灰柯种群的萌枝率、有萌个体率和幼苗相对优势度均高于金佛山方竹经营群落。综上认为,金佛山方竹经营对金佛山扁刺栲群落灌木层和草本层物种多样性产生了负面影响,并显著影响扁刺栲群落优势种种群更新和维持。

Effects of Chimonobambusa utilis management on species diversity and dominant population structures of Castanopsis platyacantha community in Jinfo Mountain

To explore the effects of Chimonobambusa utilis management on species diversity and dominant population structures of Castanopsis platyacantha community in Jinfo Mountain, the natural community of Castanopsis platyacantha and the managed community of Chimonobambusa utilis in Jinfo Mountain were used as the research object to analyze species composition characteristics, species diversity and dominant population structures in the two communities. The results were as follows:(1)A total of 84 species of vascular plants in the plots were found, belonging to 40 families and 63 genera, dominated by Lauraceae, Rosaceae, Fagaceae and Theaceae; Castanopsis platyacantha was the dominant species in the community, Schima sinensis and Lithocarpus henryi were the subordinates and Chimonobambusa utilis was the dominant species in the shrub layer, which the species composition of Castanopsis platyacantha community in Jinfo Mountain was similar to other subtropical regions.(2)The species richness of the shrub layer of the managed community was significantly lower than that of the natural community, and the Shannon-Wiener index and Pielou index of the herb layer were significantly lower than that of the natural community.(3)Dominant tree species of Castanopsis platyacantha and Lithocarpus henryi in the natural community were stable populations, but those were declining populations in the managed community, and Schima sinensis in the two communities appeared to be in decline.(4)The ratio of total sprouts to total individuals, number of multi-stemmed individuals/number of all individuals and seedling relative dominance value of Castanopsis platyacantha, Schima sinensis and Lithocarpus henryi in the natural community were higher than those in the management community of Chimonobambusa utilis. In conclusion, the Chimonobambusa utilis management has a negative impact on the species diversity with the strongest on the shrub and herb layers of Castanopsis platyacantha community in Jinfo Mountain, and the managed activities significantly affect the renewal and maintenance of the dominant species in Castanopsis platyacantha community.